俞炯奇  张土乔  兰柳和
    （浙江大学土木工程学系  杭州 310027）

[提要]  杭州市城市建设正向城东发展，为了搞清其地下35～55m处深厚圆砾层承载特性，根据已有的工程试桩实测资料分析了该深厚圆砾层作为持力层的大直径钻孔灌注桩的荷载传递机理及承载性能，为进一步合理地利用该深厚圆砾层提供一定的理论依据。
[关键词]  大直径钻孔灌注桩 桩基持力层  圆砾层 荷载传递机理 承载性能 沉降

Large-scale construction items and highrise building begin to build in the eastern part of Hangzhou. In order to clarifying the characteristic of bearing capacity of the deep-seated roundstone stratum, according to existing field test results, the author analyses the mechanism of load transferring and the characteristic of bearing capacity of large-diameter cast in place piles which beared on the deep-seated roundstone stratum. The results provide certajn theory basis for further reasonably using the deep-seated roundstone stratum.
Keywords: large-diameter cast in place piles; bearing stratum; roundstone stratum; mechanism of load transfering; bearing capacity; settlement